1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
/*
* Purpose: A minimalistic MIDI output programming sample.
* Copyright (C) 4Front Technologies, 2002-2004. Released under GPLv2/CDDL.
*
* Description:
* This program does nothing but plays a note on MIDI channel 1
* after sending a program change message.
*
* This program demonstrates how simple it's to write programs that play
* MIDI. All you need to do is assembling the MIDI message and writing
* it to the device. The MIDI format is defined in "MIDI 1.0 Detailed
* Specification" which is available from MIDI Manufacturs Association (MMA)
* (see {!hlink http://www.midi.org}).
*
* This program does timing by calling the sleep(3) system call. In some
* systems like Linux there may be better sleep routines like usleep(3)
* that provide better timing resolution.
*
* However application based timing may not be as precise as required in
* musical applications. For this reason the MIDI interface of OSS will
* provide a driver based timing approach in the near future.
*
* Please look at the "{!link MIDI}" section of the OSS Developer's
* manual for more info about MIDI programming.
*/
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <soundcard.h>
#define DEVICE "/dev/midi"
int
main ()
{
int fd;
unsigned char note_on[] = { 0xc0, 0, /* Program change */
0x90, 60, 60
}; /* Note on */
unsigned char note_off[] = { 0x80, 60, 60 }; /* Note off */
if ((fd = open (DEVICE, O_WRONLY, 0)) == -1)
{
perror ("open " DEVICE);
exit (-1);
}
if (write (fd, note_on, sizeof (note_on)) == -1)
{
perror ("write " DEVICE);
exit (-1);
}
sleep (1); /* Delay one second */
if (write (fd, note_off, sizeof (note_off)) == -1)
{
perror ("write " DEVICE);
exit (-1);
}
close (fd);
exit (0);
}
|
